/// <summary>
/// Returns an unmodifiable <seealso cref="CharArraySet"/>. This allows to provide
/// unmodifiable views of internal sets for "read-only" use.
/// </summary>
/// <param name="set">
/// a set for which the unmodifiable set is returned. </param>
/// <returns> an new unmodifiable <seealso cref="CharArraySet"/>. </returns>
/// <exception cref="NullPointerException">
/// if the given set is <code>null</code>. </exception>
public static CharArraySet UnmodifiableSet(CharArraySet set)
{
if (set == null)
{
throw new System.NullReferenceException("Given set is null");
}
if (set == EMPTY_SET)
{
return(EMPTY_SET);
}
if (set.map is CharArrayMap.UnmodifiableCharArrayMap)
{
return(set);
}
return(new CharArraySet(CharArrayMap.unmodifiableMap(set.map)));
}
